In general, a terminal, a session between a terminal and an application server or between terminals is performed according to capabilities (or setting) of the at least one terminal or the application server. This will be described in detail with reference to the accompanying drawings.
FIG. 1 is a view showing the process of performing a service based on exchanging of capability information. As shown in FIG. 1, a first UE 11 and a second UE 12 mutually check information about capabilities of the other and start a service according to the checked capabilities.
(1) First, before performing the service, the first UE 11 requests information about capabilities (referred to as ‘capability information’, hereinafter) of the second UE 12. The request for capability information is transferred to the second UE 12 via first and second networks 21 and 22.
(2) The second UE 12 checks its capabilities.
(3) Subsequently, the second UE 12 transmits its capability information to the first UE 11. The capability information of the second UE 12 is transmitted to the first UE 11 via the first and second networks 21 and 22.
(4) The first UE 11 stores the capability information.
(5) Thereafter, the second UE 12 requests capability information of the first UE 11. The request for capability information is transferred to the first UE 11 via the first and second networks 21 and 22.
(6) Then, the first UE 11 checks its capabilities.
(7) The first UE 11 transmits its capability information to the second UE 12. As mentioned above, the capability information is transmitted to the second UE 12 via the first and second networks 21 and 22.
(8) The second UE 12 stores the capability information of the first UE 11.
(9) Thereafter, the first UE 11 requests initiation of a session from the second UE 12.
(10) The second UE 12 transmits an accept response to the first UE 11 in response to the request for session initiation.
(11) Then, a session is established between the first and second UEs 11 and 12, and the service starts in the established session.
FIG. 2 is an exemplary view showing a process of performing a service based on the exchanging of the capability information. As noted in FIG. 2, while the first UE 11 is performing the service with first and second application servers 31 and 32 and the second UE 12, when the capabilities of the first UE 11 change, the information on about the changed capabilities is exchanged again and the service is re-performed according to the changed capabilities.
(1) As shown in FIGS. 1 and 2, the first UE transfers its capability information to the first and second application servers 31 and 32 via the first network 21, and the first and second UEs 11 and 12 exchange their capability information to each other via the first and second networks 21 and 22.
(2)˜(4) Thereafter, the first application server 31 provides a first service to the first UE via the first network 21, the second application server 32 provides a second service to the first UE 11, and the first UE 11 performs a third service with the second UE 12 via the first and second networks 21 and 22.
(5) Thereafter, at least one capability of the first UE 11 changes.
(6) Then, the first UE 11 informs the first application server 31 that its capabilities have changed via the first network 21.
(7) The first application server 31 transmits an acknowledge response to the first UE 11.
(8) Then, the first application server 31 requests again the capability information of the first UE 11.
(9) In response to the request, the first UE 11 transmits its capability information to the first application server 31.
(10) The first application server 31 updates the session according to the changed capabilities of the first UE 11. In detail, as shown steps 20 to 23, the first application server 31 requests session updating from the first UE 11, and the first UE transmits an accept response to the first application server 31.
(11) The first application server 31 and the first UE 11 re-start the service.
(12)˜(17) The first UE 11 informs the second application server 32 about its changed capabilities. The following procedure is the same as the steps (7) to (11).
(18)˜(23) The first UE 11 informs the second UE 12 about its changed capabilities. The following procedure is the same as the steps (7) to (11).
In the related art, as shown in FIG. 1, in order for the first and second UEs 11 and 12 to perform the service, the first and second UEs 11 and 12 should transmit their capabilities to each other. However, such radio transmission of their capabilities causes a waste of radio resources.
In addition, as shown in FIG. 2, when the capabilities of the first UE 11 change, the first UE 11 transmits its changed capabilities several times to the other party in the format of signals, to perform the service suitably according to the changed capabilities. This results in a considerable waste of radio resources, causing the first UE 11 to pay a high communication charge.
In particular, as shown in FIG. 3, when the capabilities of the first UE 11 change while the UE 11 is performing multiple services, the first UE 11 should transmit its changed capabilities for each service. This also results in a considerable waste of radio resources, causing the first UE 11 to pay a high communication fee.
Moreover, even though a portion of the capabilities of the first UE 11 changes, the first UE 11 should transmit information about its overall capabilities, not information merely about the changed portion of the capabilities, much radio resources are wasted.